/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.commons.udf.builtin;

import org.apache.iotdb.commons.udf.utils.UDFDataTypeTransformer;
import org.apache.iotdb.udf.api.access.Row;
import org.apache.iotdb.udf.api.access.RowWindow;
import org.apache.iotdb.udf.api.collector.PointCollector;
import org.apache.iotdb.udf.api.customizer.config.UDTFConfigurations;
import org.apache.iotdb.udf.api.customizer.parameter.UDFParameters;
import org.apache.iotdb.udf.api.customizer.strategy.SlidingSizeWindowAccessStrategy;
import org.apache.iotdb.udf.api.exception.UDFException;
import org.apache.iotdb.udf.api.exception.UDFInputSeriesDataTypeNotValidException;
import org.apache.iotdb.udf.api.type.Type;

import java.io.IOException;

public class UDTFEqualSizeBucketM4Sample extends UDTFEqualSizeBucketSample {

    @Override
    public void beforeStart(UDFParameters parameters, UDTFConfigurations configurations) {
        bucketSize *= 4;
        configurations
                .setAccessStrategy(new SlidingSizeWindowAccessStrategy(bucketSize))
                .setOutputDataType(UDFDataTypeTransformer.transformToUDFDataType(dataType));
    }

    @Override
    public void transform(RowWindow rowWindow, PointCollector collector)
            throws UDFException, IOException {
        switch (dataType) {
            case INT32:
                transformInt(rowWindow, collector);
                break;
            case INT64:
                transformLong(rowWindow, collector);
                break;
            case FLOAT:
                transformFloat(rowWindow, collector);
                break;
            case DOUBLE:
                transformDouble(rowWindow, collector);
                break;
            default:
                // This will not happen
                throw new UDFInputSeriesDataTypeNotValidException(
                        0,
                        UDFDataTypeTransformer.transformToUDFDataType(dataType),
                        Type.INT32,
                        Type.INT64,
                        Type.FLOAT,
                        Type.DOUBLE);
        }
    }

    public void transformInt(RowWindow rowWindow, PointCollector collector) throws IOException {
        if (rowWindow.windowSize() <= 4) {
            for (int i = 0; i < rowWindow.windowSize(); i++) {
                Row row = rowWindow.getRow(i);
                collector.putInt(row.getTime(), row.getInt(0));
            }
            return;
        }

        int minIndex = 1, maxIndex = 1;
        int maxValue = rowWindow.getRow(1).getInt(0);
        int minValue = rowWindow.getRow(1).getInt(0);
        for (int i = 2; i < rowWindow.windowSize() - 1; i++) {
            int value = rowWindow.getRow(i).getInt(0);
            if (minValue > value) {
                minValue = value;
                minIndex = i;
            }
            if (maxValue < value) {
                maxValue = value;
                maxIndex = i;
            }
        }
        if (minIndex == maxIndex) {
            maxIndex = rowWindow.windowSize() - 2;
        }

        Row row = rowWindow.getRow(0);
        collector.putInt(row.getTime(), row.getInt(0));
        if (maxIndex < minIndex) {
            row = rowWindow.getRow(maxIndex);
            collector.putInt(row.getTime(), row.getInt(0));
            row = rowWindow.getRow(minIndex);
        } else {
            row = rowWindow.getRow(minIndex);
            collector.putInt(row.getTime(), row.getInt(0));
            row = rowWindow.getRow(maxIndex);
        }
        collector.putInt(row.getTime(), row.getInt(0));
        row = rowWindow.getRow(rowWindow.windowSize() - 1);
        collector.putInt(row.getTime(), row.getInt(0));
    }

    public void transformLong(RowWindow rowWindow, PointCollector collector) throws IOException {
        if (rowWindow.windowSize() <= 4) {
            for (int i = 0; i < rowWindow.windowSize(); i++) {
                Row row = rowWindow.getRow(i);
                collector.putLong(row.getTime(), row.getLong(0));
            }
            return;
        }

        int minIndex = 1, maxIndex = 1;
        long maxValue = rowWindow.getRow(1).getLong(0);
        long minValue = rowWindow.getRow(1).getLong(0);
        for (int i = 2; i < rowWindow.windowSize() - 1; i++) {
            long value = rowWindow.getRow(i).getLong(0);
            if (minValue > value) {
                minValue = value;
                minIndex = i;
            }
            if (maxValue < value) {
                maxValue = value;
                maxIndex = i;
            }
        }
        if (minIndex == maxIndex) {
            maxIndex = rowWindow.windowSize() - 2;
        }

        Row row = rowWindow.getRow(0);
        collector.putLong(row.getTime(), row.getLong(0));
        if (maxIndex < minIndex) {
            row = rowWindow.getRow(maxIndex);
            collector.putLong(row.getTime(), row.getLong(0));
            row = rowWindow.getRow(minIndex);
        } else {
            row = rowWindow.getRow(minIndex);
            collector.putLong(row.getTime(), row.getLong(0));
            row = rowWindow.getRow(maxIndex);
        }
        collector.putLong(row.getTime(), row.getLong(0));
        row = rowWindow.getRow(rowWindow.windowSize() - 1);
        collector.putLong(row.getTime(), row.getLong(0));
    }

    public void transformFloat(RowWindow rowWindow, PointCollector collector) throws IOException {
        if (rowWindow.windowSize() <= 4) {
            for (int i = 0; i < rowWindow.windowSize(); i++) {
                Row row = rowWindow.getRow(i);
                collector.putFloat(row.getTime(), row.getFloat(0));
            }
            return;
        }

        int minIndex = 1, maxIndex = 1;
        float maxValue = rowWindow.getRow(1).getFloat(0);
        float minValue = rowWindow.getRow(1).getFloat(0);
        for (int i = 2; i < rowWindow.windowSize() - 1; i++) {
            float value = rowWindow.getRow(i).getFloat(0);
            if (minValue > value) {
                minValue = value;
                minIndex = i;
            }
            if (maxValue < value) {
                maxValue = value;
                maxIndex = i;
            }
        }
        if (minIndex == maxIndex) {
            maxIndex = rowWindow.windowSize() - 2;
        }

        Row row = rowWindow.getRow(0);
        collector.putFloat(row.getTime(), row.getFloat(0));
        if (maxIndex < minIndex) {
            row = rowWindow.getRow(maxIndex);
            collector.putFloat(row.getTime(), row.getFloat(0));
            row = rowWindow.getRow(minIndex);
        } else {
            row = rowWindow.getRow(minIndex);
            collector.putFloat(row.getTime(), row.getFloat(0));
            row = rowWindow.getRow(maxIndex);
        }
        collector.putFloat(row.getTime(), row.getFloat(0));
        row = rowWindow.getRow(rowWindow.windowSize() - 1);
        collector.putFloat(row.getTime(), row.getFloat(0));
    }

    public void transformDouble(RowWindow rowWindow, PointCollector collector) throws IOException {
        if (rowWindow.windowSize() <= 4) {
            for (int i = 0; i < rowWindow.windowSize(); i++) {
                Row row = rowWindow.getRow(i);
                collector.putDouble(row.getTime(), row.getDouble(0));
            }
            return;
        }

        int minIndex = 1, maxIndex = 1;
        double maxValue = rowWindow.getRow(1).getDouble(0);
        double minValue = rowWindow.getRow(1).getDouble(0);
        for (int i = 2; i < rowWindow.windowSize() - 1; i++) {
            double value = rowWindow.getRow(i).getDouble(0);
            if (minValue > value) {
                minValue = value;
                minIndex = i;
            }
            if (maxValue < value) {
                maxValue = value;
                maxIndex = i;
            }
        }
        if (minIndex == maxIndex) {
            maxIndex = rowWindow.windowSize() - 2;
        }

        Row row = rowWindow.getRow(0);
        collector.putDouble(row.getTime(), row.getDouble(0));
        if (maxIndex < minIndex) {
            row = rowWindow.getRow(maxIndex);
            collector.putDouble(row.getTime(), row.getDouble(0));
            row = rowWindow.getRow(minIndex);
        } else {
            row = rowWindow.getRow(minIndex);
            collector.putDouble(row.getTime(), row.getDouble(0));
            row = rowWindow.getRow(maxIndex);
        }
        collector.putDouble(row.getTime(), row.getDouble(0));
        row = rowWindow.getRow(rowWindow.windowSize() - 1);
        collector.putDouble(row.getTime(), row.getDouble(0));
    }
}
